Freund, R. J., & Littell, R. C. (1991). SAS System for regression (2nd edition.). SAS Institute.
Cita Chicago Style (17a ed.)Freund, Rudolf J., y Ramón C. Littell. SAS System for Regression. 2nd edition. Cary, NC: SAS Institute, 1991.
Cita MLA (8a ed.)Freund, Rudolf J., y Ramón C. Littell. SAS System for Regression. 2nd edition. SAS Institute, 1991.
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